Various kinds of cards are becoming more prevalent for such purposes as security (for example, identification cards and badges), financial transactions (credit and debit cards), driver's licenses, and so forth. These cards are typically made of plastic but may also comprise paper or cardboard. The cards may have printed or embossed characters, magnetic strips, and/or other images or indicia on one or both faces. Although the length and width of these cards have been substantially standardized, card thicknesses may vary considerably.
FIG. 1 shows a plastic card 10 typical of those in use today. The card 10 has a front face 12, a rear face 14 carrying a longitudinally-extending magnetic strip 16, and a generally rectangular geometry comprising a pair of opposed, parallel, longitudinally-extending long edges 18 and 20 and a pair of opposed, parallel, transversely-extending short edges 22 and 24. The card 10 has a longitudinal or major central axis 26 and a transverse or minor central axis 28.
Conventional printers for printing information on discrete cards such as that shown in FIG. 1 comprise a linear series of processing stations or modules generally including a card feeder, a card flipper or inverter, a print mechanism and a card discharge station. A typical card feeder has a vertical hopper designed to receive a supply of horizontally oriented cards stacked one on top of another. A lifter under the stack urges the stack upwardly to progressively raise the stack as cards are successively withdrawn from the top. The card feeder supplies the cards to the card inverter that rotates each card as necessary and transfers it to and from the card print mechanism in a sequence of steps whereby one or both faces of the card are printed. In conventional printers, the card inverter rotates the card about its shorter or minor central axis 28 (FIG. 1). The print mechanism typically comprises a thermal printhead cooperating with a thermal transfer ribbon or dye sublimation ribbon to print information on a face of each card as the card is fed lengthwise past the print mechanism.
The present invention addresses several drawbacks of conventional card printers. For example, because the various stations or modules of conventional card printers are arranged in a row, such printers take up considerable desktop space. Moreover, because the cards are stored as a vertical stack in the card supply hopper, conventional card printers tend to be tall. Contributing to their height (as well as to their length) are the card inverters or flippers that rotate the cards around their minor axes. Besides using space inefficiently, existing card printers, because of their size, cost more to manufacture requiring, for example, larger, more expensive enclosures.
In addition, most conventional card feeders have a fixed slot or gate at the discharge of the card supply hopper through which the cards are passed out of the hopper. The width of the gate is usually set to accommodate one particular card thickness and must be manually readjusted to accept cards having other thicknesses. This is undesirable because it is difficult to measure and to set a gate to accurately feed cards of widely varying thicknesses without double feeding. Double feeding occurs when the card being fed from the top of a stack of cards drags the next card below along with it.